- This article is about the physical form of the Ocean Spirit. For the koi incarnation of the Moon Spirit, see Tui. For the large fish found off the coast of Kyoshi Island, see Elephant koi.
|"Our strength comes from the Spirit of the Moon; our life comes from the Spirit of the Ocean. They work together to keep balance."|
|— Yue to Aang and Katara.|
La, also known as the Ocean Spirit, is one of two spirits which reside in the Spirit Oasis in the Northern Water Tribe's capital city at the North Pole, taking the form of a black koi fish with a large white spot on its head. Together with its counterpart Tui, La was among the first spirits to come to the mortal world, and the pair have kept balance ever since in an "eternal dance" of push and pull.
Thousands of years before the Hundred Year War, La and Tui decided to manifest themselves into the physical world to benefit mankind, taking up residence in an alcove of Agna Qel'a. They created the oasis in the North Pole and took the form of two koi fish. Thereafter, the Spirit Oasis became the city's most treasured landmark.
Centuries later, the Fire Nation initiated a siege on the Northern Water Tribe, during which Admiral Zhao captured and killed Tui, the Moon Spirit. With its counterpart gone, La was left swimming around frantically in the pool. Making eye contact with La, Aang entered the Avatar State and walked into the water of the Spirit Oasis, where the Ocean Spirit started swimming around him. The two fused to form Koizilla, a colossal fish-like figure, and quickly annihilated the Fire Nation land forces and navy fleet with their superior waterbending.
When La noticed that Tui had been revived by Princess Yue's sacrifice, the spirit ceased its destructive rampage and separated from Aang, leaving him at the city's ice walls, and returned to the Spirit Oasis. On its way, it encountered a dueling Zhao and Zuko; to avenge the attack on Tui, the Ocean Spirit formed an arm out of water and dragged Zhao below the surface, ultimately imprisoning him in the Fog of Lost Souls.
Koizilla was the being that La became when it joined with Aang in the Avatar State. Made entirely of water and light, this destructive creature is literally the wrath of the ocean in physical form. In this state, La was capable of wiping out dozens of Fire Nation soldiers and tanks, as well as Zhao's invasion fleet.
Avatar: The Last Airbender
Book One: Water (水)
- "La" ( ) means "pull" in Mandarin Chinese, compared to "Tui" ( ), which means "push". According to Princess Yue, the ancient waterbenders saw the tides push and pull, giving a hint to the Ocean and Moon Spirits' existence in the tribe.
- Tui and La resemble the Chinese yin-yang symbol, a symbol of balance and Taoism, in their coloring and mannerisms. La represents Yin in appearance, being associated with cool, dark, and watery, and Yang in personality, being associated with being active and strong. Additionally, Aang pictured the two as a yin-yang symbol shortly before entering the Spirit World, and Koh specifically pointed this out when telling Aang about the identity of Tui and La.
- The creators of Avatar nicknamed the fusion of La and Aang "Koizilla".
- The Ocean Spirit's second form greatly resembles the Night-walker form of the Forest Spirit from Hayao Miyazaki's film Princess Mononoke.
- A petroglyph depicting Tui and La encircling each other was present on the stone wall behind the waterfall in Tarrlok's office.